Cooling device for pistons



July 21, -1936.

F. FRELIN COOLING DEVICE FOR PISTONS v Filed Aug. 29,` 1934 Patented July 2l, 1936 COOLING DEVICE FOB. PISTONS Frltio! Frelin, Philllpsbur N. J., aslignor to Ingersoll-Band Company. Jersey City, N. J., a corporation of New Jersey Application August 29, 1934, Serial No. '141,912

2 Claims. (Cl. 1234176) This invention relates to cooling devices, and more particularly to cooling devices for pistons of internal combustion engines and similar machines in which the piston head is exposed to 5 extremely high temperatures. A

The invention is particularly applicable to pistons of large diameter of which the central areas oi the piston head are located too tar from the cylinder wall to permit of the heat in such portions to be removed at a suiciently rapid rate to prevent distortion, fracture or burning of the head.

It is an object of the present invention to maintain the temperature of the piston head within 16 safe limits.V

Another object of the invention is to utilize a portion of the oil employed for lubricating the various bearings oi' the engine as a medium for effecting the removal oi heat from the piston 2p head.

Other objects will be in part obvious and inpart pointed out hereinafter.

In the drawing accompanying this speciiica-v tion and in which similar reference numerals 2'5 refertosimilarparts,

ton and 2i a connecting rod which is connected tothepistonbyawristpin 22.

The connecting rod 2l is provided with the usual passage 23 for conveying oil. under pres- 35 sure, to the surface of the wrist pin for lubricating its bearings and, in the present instance. the wrist pin 22 is provided with a bore which extends entirely therethrough to form a chamber 24 for oil which is admitted into the chamber 24 by 40 passages 25, in the wrist pin, communicating with the passage 23. A

0n the inner surface of the pistonare the usual diametrically opposed bosses 26 having bores 21 into which the ends oi the wrist pin extend. At 45 the outer ends of the bores 21 are enlarged recesses 28 containing plates 29 which seat against the bottoms of the recesses 28 and cooperate therewith to seal the outer ends of the bores 21. The plates 29 are preferably constructed of 50 flexible material. They are of. dish-shape having hub portions 30 into which are threaded the ends of a rod 3i whereby the plates are held securely in position.

Preferably, the wrist pin 322 is somewhat short- 55 er than the distance between the outer ends oi the bores 21 so that oil may pass freely from the ends oi the chamber 24 into all portions oi' the. spaces within the plates 29.

In accordance lwith the practice of the invention, the piston is provided with an internal wall 5 32 between the bosses 26 and the head 33 of the piston. 'Ihe wall 32 is preferably arranged in substantial parallelism withthe outer surface oi,

the head 33. It spans the space between the bosses 26 and has depending portions 34 at its l0 sides which join the wall to the bosses and combine therewith and with the wall of the piston to denne depressed portions 35 of a chamber 36 oi which the portionV 31 lying between the wail 32 and the head 33 of the piston constitutes a shal- 15 low portion.

Communication is afforded between the oil chamber 24 in the wrist pin and the chamber 36 by passages 38 which open with one end into the bottom oi the depressed portions 36 of the cham- 20 ber 36 and with their other ends into the outer ends of the bores 21. Ports 39 in the wall 32 aiiord an outlet for the oil from the chamber 36.

In practice, when the engine of which the piston is" a part is in operation, oil iiows from 25 the ends of the chamber 24 through the passages 33 into the chamber 36. thence through the ports to return to the crank pan or oil reservoir. By suitably proportioning the various ports and passages which supply oil to the chamber 36'and 30 convey it therefrom the said chamber may be constantly maintained iilled with a moving body of oil which ca: ies away the heat transmitted thereto by the head 33. In consequence. the head will be protected against the eiects oi extreme temperatures incident to combustion without. however, lowering the temperature of the head to a value sufiiciently low to impair the performance of the engine.

After a period of operation, that is when the 40 engine stands idle and the delivery of oil to the chambers 24 and 36 ceases, the oil lying in the shallow portion 31 of the chamber 36 above the wall 32 will drain through the ports 39. Only the depressions as wm men remain sued with oil which, at the beginning oi a subsequent period oi operation of the engine, will immediately be cast against the piston head and prevent overheating thereof until the chamber 36 is again iilled and. the oil circulates through the chamber as aconstant stream.

I claim: 1. In a cooling device, the combination of a Vpistonaudaccnnectingrod,awristpinconnectu ing thetwo and having a bore therethrough.tol

form an oil chamber. and a cooling chamber in the piston comprising a shallow portion and a plurality of deep portions, said piston having passages leading from the oil chamber to the deep portions of the cooling chamber to convey oil to the cooling chamber and having an outlet passage intermediate the deep portions to convey oil from the cooling chamber.

2. In a cooling device, the combination .otl a piston and a connecting rod. a wrist pin connectber to the lowermost 'portions of the depressions and said wall having ports to convey oil from the cooling chamber.'

FRITJOF FREUN. 

